Wagner et al. used an interrupted times series design to examine changes in worker productivity after the institution of a worker incentive plan. In addition to measuring productivity, they also examined other information in order to rule out alternative explanations of their results. They were able to rule out _______ because _______.
A) history; no significant event occurred around the time of the program's start
B) instrumentation; the manner of measuring productivity didn't change
C) selection; of an absence of significant worker turnover
D) all of the above

Question

Quizplus · Accepted Answer

Wagner et al. were able to rule out history as a factor because there was no significant event around the time of the incentive plan's implementation. They were able to rule out instrumentation because the method of measuring productivity didn't change. They were able to rule out selection because there was an absence of significant worker turnover. Therefore, the best choice is D, which includes all of the above.

Wagner Et Al